Oil lubricating systems for engines typically have consisted of a circuit for circulating oil from the oil sump of the engine to the working components of the engine and then back to the sump, cooling such components and removing contaminants entrained in the oil. Such working components generally include the pistons, cylinders, piston rings, crankshaft, connecting rods, camshafts and various bearings therefor. Such contaminants include the effects of abrasion, adhesion, corrosion and fretting of engine components. Such circuit further is typically provided with a pump for circulating the oil through the system, having a bypass including a relief valve, and a filter for removing such contaminants. Such filters, however, generally have been found not to be entirely effective in the removal of such contaminants. As a remedy for such ineffective removal of contaminants, it has been recommended and the general practice of simply periodically changing the oil in such systems with clean oil. Such practice of replacement of used oil not only is expensive and inefficient but time consuming. It further is undesirable in that it contributes to increased fuel energy consumption and presents disposal problems which affect the environment. Accordingly, it is the principal object of the present invention to provide a novel filter and method of finer filtering fluids and particularly motor oils used in lubricating engines, thus requiring less replacement and disposal of used oils.